Deleting old coupon codes

Hello,
I wish to delete old coupon codes, and I am not able to do it. I believe that I am doing something wrong, and asking for assistance.
After logging in as admin, I create a new code for one product. I save it as active.
I am logging off, and logging on again as a "customer".
If I am clicking on "discount coupons", all the old coupons appear, but not the new one!
I am trying to delete the old coupons, but they do not show anywhere, not in "active, inactive or all" option.
Is there any way to delete the old ones?
How can I tell my customers about the new coupon?
Thanks in advance for assistance!

Are they "not showing" because they're "on the next page"?

Thank you for replying DrByte,
I am attaching 3 screenshots. The Active, Inactive and All Coupons. As soon as I click on All Coupons, I am receiving zero, and the window becomes "Active" as it can be seen.
Attachment 17469
Attachment 17470
Attachment 17471

Connecting as a customer, at checkout I receive the following options:
Attachment 17472

Of course, just one of them works, and I wish to delete the others, but I cannot find the way to do it.
I hope that now it is clearer.

Your "options" as a customer are "previously-remembered" data that you had typed into that field ... remembered by your browser. Those options are NOT coming from Zen Cart.

If you visit the same page on another browser you will not find those codes listed there.
To remove them from your browser's history, go to your browser's auto-fill settings and remove them.

Thank you for replying DrByte,
You are perfectly right!!! Usually, I use Firefox, and tried it a moment ago from Chrome. Indeed, nothing appeared!!! It works perfectly! :)
It shows you my ignorance...
So, now I have the initial problem:
My idea was: I wish to give a discount for one product, for a predetermined time. Changing the product and code every month or week. The idea was that only the logged in customers will be able to see which product has a discount this week.
The guy who has installed the ZC made it almost perfect: There is a picture on the main page, and only if you click on it, you are be able to see the discounts. This way, the curious customer clicks on this button / picture, and he is being asked to log in. Up to here, it works perfect.
However, is there any way to show him which product has a coupon code this week, and what it is the code?
As far as I could understand, I have to email him the code.
What I need is a "call to action", as up to emailing him, he can give up, not even talking about the issue that he doesn't see which product is the one I promote.
Do you have any idea or suggestion? Is it again my ignorance???

Many thanks again!!!

There's not currently any built-in way to automatically display all your coupon codes to your shoppers, whether logged in or not.

You could write custom code to query the coupons and coupon-restrictions data to identify which product/s are eligible for the currently active coupons.

I think that I've succeeded to do it, even that it is a primitive way to do it.
Firstly, I've used the usual way for setting up a discount coupon, and I've copied the code. I made a txt file with the code embedded.
Secondly, I made changes in coupon's PHP.
Now, when I click on "coupons button", I get the code.
It works perfect!

Here is how it looks:
Attachment 17480
And at checkout:
Attachment 17481